Did you ever figure out what was causing the original whistling problem?

 

i was hoping there was a solution...i have the same problem and it's driving me crazy. It started when I hooked up a K&N intake. The weird thing is that my buddy is running the same set up on his 2010 with no whistle, mine is a 2011. The only difference between his and mine was his intake was bought used from a guy who hydrolocked. Should i submerge the filter in water and let it sit for a while? I disassembled and reassembled the intake...still there.

 

Try changing the rubber o ring ( gasket ) on the back side of the throttle body!!!!